Spark-plug.



H. 1. BERTHOLD.

SPARK PLUG.

Patented June 15, '1915.

pm i f\ f ,LA ww j 7 j l l .0 B045 /l 5 l "VrWITNESSES P gw HENRY J. BEE-WHOLE,4 OF IRVINGTON, NEW JERSEY:

slum.nantais'.`

Application led June 18, 1912.

To nl! @from it may con cern:

` llo it known that I, HENRY J. BERTI-TOLD, a citizen of.' the llnited States, residing at lrvington. in the county of Essex and State of New Jersey, have invented certain Im proveinents in Spark-lungs, oi iviich the following is a specification.

The objects of this invention are to provide in a spark plug; a binding post of simple and inexpensive construction which cannot work loose and become inelicient by repeated screu'iiuqA on and oil oi the binding screw which clamps the circuit wire; to prevent the lcaldigre of gas, around the central pin or electrode ot' the spark plug; to secure a tight hrm seating of the porcelain in its bushingr and oli said bushing in the shell, so as to prevent leakage and looseness; to pro vide a spark plug which can be rea dil)7 taken apart for cleanirgx or the like; to provide readily adjustable means Whereb)7 the spark gap between the electrodes inajv be revir lated; to provide a pl iralitv of paths for the spar-li to span said gap; to secure siniplici't'v of construction and economi7 of manutacture`r and to obtain ther advantages and results ma);7 be brought out in the followingr description.

Referring to the accompanying drawings7 in "which like numerals of reference indicate the saine parts throughout the several views, Fiejure l is a view in elevation of my iniproved spz'irl; plug; Fig. 2 is a longitudinal sectional view of the saine applied, and on larger scale; 8 is a cross-sectional view on line ,^L- of Fig. 2; Fig. 4l is a crossA sectional view on line B--B of Fig. 2 and Fie'. 5 isa perspective vieu` of the. bridge or gap plate,

ln the specific embodiment of the inven- `tion illustrated in said drawings, i indi entes the evlinder Wall ot an internal coin-- bustion engine into which the shell 2 is secured bv means of exterior threads 3 at its lower endi said end beingreduced diametrieallv to prmidc an annular-Shoulder 4 above the saine which rests against an asbestos gasket or other packingV 5 between the said shoulder l and the ivall L so that an impers -vious foin?. is provided ther-eat, Above the said shoulder l is an exteriorly angular por tion (i to which a ureueh or other suitable tool may oc :applied to insert or remove the said shell 2 'with respect to the cylinder, as inrni'umeii.

'lhs shell is loiigitndinall),T chainhered Specification ox" Letters Iatent.

Patented il une 15, 1915. smal nu, 704,283(

or bored, as at 7, the diameterof its chamber increasing as at 8, at the outer or Wrenclr receiving end of the shell. he Wall. of this increased bore or chamber is preferably a rustalted conical surface Haring outward and having threads 5l out into said conical surface, so. that a bushing l0, eXteriorly tapered and threaded to correspond, may be screwed into or out of the shell 2. By cutm ting the threads upon frustated conical surfaces as described, the resistance to shear is lfept high and a-tight joint is obtainedv to prewnt the passage' of gas when the parts are operativebT assembled, and at the same time onljty mere start or partial rotation oi one part with respect to the other is required to loosen them sulicicntly to he readily separated ov hand. In order to suppl;7 a grip for a Wrench, the bushing 10 has an angular portion 1l bevond its said threads i2, shown. Said bushing l0 furthermore provides an interior conical or tapering surface, the smaller end of which is at the outer or ivrenchreeeiving end of the bushing, said surface being adapted to wedgingly engage the correspondined)vv tapered outer surface 13 ofA a porcelain or other insulating member il inserted in the bushing, and hold said porcelain tightly and firmly. Inward displacement of the porcelain 14 is prevented liv inwardljvY curlingr or crimping over aga inst an appropriate shoulder l5 ot' the insulatingry member, as at 17, a reduced or thinned collar i8 projecting originali).7 from the inner end oi the bushing 10 and preferablv being an integral part thereof. ln manufacture. the engaging and taliering surfaces of the porcelain and bushingY are `around or machined and the two parts then iorced firmly together and clamped in such relation b v the crimped collar l? as descrilied. This provides a perfectly impervious joint to 'the passage of the gases, and a structure which it can readily be seen is 'free from an)7 possibilit;r of the porcelain .14 boing blown out: by the pressure of gases caused liv the explosions within the cylinder.

The, upper or outer end if) of the porcelain 1li is shaped or made angular in cross-sectioin here shown as hexagonal, and' is pro- `vided inunrdl;Y bevond said angular end 19 'with a shoulder l0 Jfacing away from said end Il!) and. which .l have shown as formed lo' entrino; an annular `groove Qi. into and around said porcelain il, although it might be :formed in angv other Way mechanical skill lll) diie@ @ms mi 3, which me mma upwardly o1 i50- m@ she 2; as Showm and 'om mamies. of .munis of fne second or @washing e'ec 'im-0m. Tjie. pin 26 forming the des? and. @mi

l daim iS:

said am-dm ma?, plata and,

gy to the by'e 28g m the l 4f; im Spad; pug., an insulating ffgmbe Sectlon and. A

hvng; an en'dngulm in @rms provce with -a peripheral shu'der v @am :said angular emL a binding post having im; angular baise pata adanii abut aganstsa and ,of `the insfuatng member, and a Gorreslprmdngy' angular cap mosng said base'pabe and end and hmng its edges 5 lin u spark plug-a shall aap. bs'.

mi V2 @hdl Maf-wing; m

ing Said eieczmde and arms proheil iis @enigmi opening Y middle, poitioi ii'w the said y v hereby the pars of We midd'ie p0rwn. mid gioia ifiziy bem toward L f www@ ih@ sieii bridge having mg@ the dial slots extending from its central opening through said middle portion into the said arms, whereby the parts of the middle p0rtion between said slots may be spread apart and pressed together.

7. In a spark ping, an insulating member having an and anguiar in crow-section, a Conuctr supported by the insulating member ifi-flving an anguiar particu adjacent said end., and a correspmidingiy angular cap engaging said anguiar prtions of the conue'wr af the insuiatl'ig member.

HENRY J, BERTHOLD. 

